1. Field of the Invention
The present invention relates to a combustion apparatus for a refuse incinerator.
2. Description of the Related Art
Conventionally, a combustion apparatus for a refuse incinerator has been generally composed of drying grates 21, combustion grates 22 and post-combustion grates 23 as shown in FIG. 3. In this apparatus, the drying grates 21, combustion grates 22 and post-combustion grates 23 are driven by independent driving sources respectively.
As shown in FIG. 4, attempts are made to reduce the cost of combustion by causing the combustion grates 22 to have the same function as that in a post-combustion zone with increase of the combustion rate of grates.
The combustion grates 22 are composed of mobile grates 4 and immobile grates 5. A plurality of rows of the mobile grates 4 and immobile grates 5 are alternately arranged in the direction of the breadth of the combustion apparatus of the incinerator. The mobile grates 4 are mounted on mobile girders 6 which are shuttled by a hydraulic cylinder 9. The immobile grates 5 are mounted on the immobile girders 7. Refuse is successively transferred by the shuttling motion of the mobile grates 4 toward the downstream side, and during transferring of the refuse, the refuse is combusted.
In this case, since the transferring speed of the refuse in the combustion zone at the front stage of the combustion apparatus is equal to that in the post-combustion zone at the rear stage of the combustion apparatus, the accumulation of the refuse or ash in the post-combustion zone becomes extremely small. As a result, the grates are exposed in the incinerator.
Therefore, there have occurred problems that the temperature of the grates is extraordinarily enhanced by heat radiation of combusting gases inside the incinerator, that molten metals stick to the surfaces of the grates, and that emergency stop of the operation of the combusting apparatus is caused by decrease of service life of the grates or by sticking of the grates to each other.